Note 4 - Inventory - Inventory (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Raw materials and component parts	$ 2,923,247	$ 2,945,427
Work-in-process	3,367,632	2,800,699
Finished products	4,876,415	2,183,170
Total inventory	11,167,294	7,929,296
Less: inventory reserves	230,506	250,606
Net inventory	$ 10,936,788	$ 7,678,690

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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